Connection assembly, battery module, battery pack, and device

Abstract

The application relates to the technical field of energy storage devices, and in particular, to a device, a battery pack, a battery module, and a connection assembly. The connection assembly includes: a connecting sheet; an insulating film which is connected to a plurality of the connecting sheets, where the insulating film is provided with a weakened portion. In the present application, the weakened portion has weaker strength. When force is applied, deformation and/or breakage occur/occurs at the weakened portion, thereby reducing the risk of tearing at other positions of the insulating film, improving the flexibility of the connection assembly, and reducing the risk of exposure of the connecting sheet due to the tearing of the insulating film, such that the risk of short circuit between the connecting sheet and other conductive component is reduced, and the safety performance of the battery module is improved.

What is claimed is: 
     
         1 . A connection assembly for a battery module, wherein the connection assembly comprising:
 a connecting sheet, the connecting sheet electrically connect battery cells constituting the battery module; and   an insulating film, a plurality of the connecting sheets are mounted onto the insulating film, and are insulated from each other;   wherein the insulating film is provided with a weakened portion, and when the insulating film is subjected to external force greater than a specified value, the insulating film is deformed and/or broken at a position of the weakened portion.   
     
     
         2 . The connection assembly according to  claim 1 , wherein the weakened portion comprises a first body portion and a first arc portion; and
 along an extension direction of the first body portion, an end of the first body portion are connected to the first arc portion.   
     
     
         3 . The connection assembly according to  claim 2 , wherein a section of the first body portion is rectangular, the first arc portion is a circular arc structure, and the first arc portion is tangent to two side walls of the first body portion; and
 a diameter D of the first arc portion is equal to a width dimension a of the first body portion.   
     
     
         4 . The connection assembly according to  claim 2 , wherein the first arc portion is a circular structure having an opening, and the first arc portion communicates with the first body portion through the opening; and
 a diameter D of the first arc portion is greater than a width dimension a of the first body portion.   
     
     
         5 . The connection assembly according to  claim 1 , wherein the insulating film comprises a first insulating film and a second insulating film;
 along a height direction of the connection assembly, at least part of the connecting sheet is located between the first insulating film and the second insulating film; and   the first insulating film and the second insulating film each are provided with the weakened portion, and along the height direction of the connection assembly, the weakened portion of the first insulating film is arranged corresponding to the weakened portion of the second insulating film.   
     
     
         6 . The connection assembly according to  claim 5 , wherein along the height direction of the connection assembly, a projection of the weakened portion of the first insulating film at least partially coincides with a projection of the weakened portion of the second insulating film. 
     
     
         7 . The connection assembly according to  claim 6 , wherein a center line of the weakened portion of the first insulating film coincides with a center line of the weakened portion of the second insulating film. 
     
     
         8 . The connection assembly according to  claim 5 , wherein along the height direction of the connection assembly, the weakened portion of the first insulating film and the weakened portion of the second insulating film are arranged in a staggered manner. 
     
     
         9 . The connection assembly according to  claim 8 , wherein a minimum distance between the weakened portion of the first insulating film and the weakened portion of the second insulating film is t, and 0<t≤0.5 mm. 
     
     
         10 . The connection assembly according to  claim 9 , wherein along the height direction, the first insulating film and the second insulating film overlap together, and an overlapping part of the two is between the weakened portion of the first insulating film and the weakened portion of the second insulating film. 
     
     
         11 . The connection assembly according to  claim 5 , wherein the weakened portion of the first insulating film is provided as a first through hole, and the weakened portion of the second insulating film is provided as a second through hole. 
     
     
         12 . The connection assembly according to  claim 11 , wherein a width dimension a of the first through hole is smaller than a width dimension b of the second through hole. 
     
     
         13 . The connection assembly according to  claim 12 , wherein a length dimension L1 of the first through hole is greater than a length dimension L2 of the second through hole. 
     
     
         14 . The connection assembly according to  claim 13 , wherein
 the length dimension L2 of the second through hole and the length dimension L1 of the first through hole satisfy: L2≤L1−2*D, wherein D is the diameter of the first arc portion.   
     
     
         15 . The connection assembly according to  claim 5 , wherein the first insulating film is provided with a first via hole, and the second insulating film is provided with a second via hole; and
 along the height direction of the connection assembly, a connecting portion of the connecting sheet is between the first via hole and the second via hole.   
     
     
         16 . The connection assembly according to  claim 1 , wherein the connection assembly further comprises a circuit board, the circuit board is configured to be electrically connected to the connecting sheet, and the insulating film connects the circuit board and the connecting sheet together. 
     
     
         17 . The connection assembly according to  claim 16 , wherein the weakened portion is located between the adjacent connecting sheets, and/or the weakened portion is located between the connecting sheet and the circuit board. 
     
     
         18 . A battery module, wherein the battery module comprising:
 a battery cell, wherein the battery cell comprises electrode leads; and   a connection assembly, wherein the connection assembly is the connection assembly according to  claim 1 ;   a connecting portion of the connecting sheet is configured to connect the electrode leads of the battery cell.   
     
     
         19 . A battery pack, wherein the battery pack comprises a box body and the battery module according to  claim 18 , and the battery module is fastened in the box body. 
     
     
         20 . A device, using a battery cell as a power supply, wherein the device comprising:
 a power source, the power source is configured to provide driving force for the device; and   the battery module according to  claim 18  configured to provide electrical energy for the power source.